Abstract: An optical pickup actuator and an optical recording and/or reproducing apparatus using the same. The optical pickup actuator includes a base having a holder positioned at one side of the base, a blade having an objective lens mounted at one side of the blade and a guide groove, a magnetic driving portion which includes at least one fine pattern coil installed across the guide groove, magnets arranged to be embedded in the guide groove opposite to each other at both sides of the FPC, and elastic supporting members having one end coupled to the holder such that the blade is movably supported.

Abstract: In a data recording apparatus, values of parity bits to be additionally provided every one predetermined length block in data obtained by demodulating the original data are determined so as to satisfy a part of or an entire the predetermined run length limitation rule in ranges of a current predetermined length block, the plurality of parity bits, and a next predetermined length block that is positioned next to the current block. The parity bits having the values are additionally provided to the current block.

Abstract: An objective lens of an optical pick-up is ascended from the disc Far position towards the disc Near position at a constant velocity, and a peak bottom detector detects levels between the peak to the bottom (peak-to-bottom levels) of focus error signals obtained during the focus movement. A servo processing microcomputer counts the number of focus error signals having a peak-to-bottom level not smaller than the predetermined minimum level, out of all peak-to-bottom levels obtained during the focus movement across the recording layer of a disc, and defines the count value as the number of the recording layers of the disc. This allows correct determination of the number of recording layers of recording medium while not being affected by variation in property of the instruments, variation in reflectivity of recording medium, variation in the ambient temperature and fake pulse corresponded to waviness in focus error signal.

Abstract: An optical pickup apparatus used in an optical data recording/reproducing apparatus for reading/reproducing data on an optical recording medium, including a light source, a diffracting device configured to transmit a light beam and to diffract a light beam reflected from the optical recording medium, an optical device having a reflecting portion and a transmitting portion configured to reflect one part of the light beam emitted from the light source and to transmit another part of the light beam to the optical recording medium and from the optical recording medium, and a photodetecting device to detect the light beam from the optical recording medium for signal light detection, and the light beam reflected by the reflecting portion of the optical device for monitor light detection of the light source.

Abstract: A slider system have been developed to aid in the spacing between read/write heads and the storage medium, and a grating antenna amplifier has been developed to improve illumination spot size and polarization characteristics. The grating antenna can be attached to a grayscale slider to obtain a distance between the illumination spot and antenna that lies in the near field region.

Abstract: An information recording medium having at least a read only area and a recording and reproducing area is composed of at least: a substrate; a recording layer formed on the substrate so as to record and reproduce information; and a light transmission layer having transparency formed on the recording layer. The information recording medium is further characterized in that a wobbling groove corresponding to the read only area and another wobbling groove corresponding to the recording and reproducing area is formed on the substrate without overlapping with each other, the recording and light transmitting layers are continuously adhered over at least two areas of the read only area and the recording and reproducing area, reflectivity of the recording layer is more than 5%, and a push-pull signal output T3 reproduced from the read only area and another push-pull signal output T4 reproduced from the recording and reproducing area before recording satisfies relations of T3?0.1, T4?0.1 and 1.5?T3/T4?0.5.

Abstract: In a disc drive device (10) described as a specific embodiment of the present invention, AC0 to AC12 of ADIP cluster address are associated with AU6 to AU18 of an address unit. A high-order digit of a sector address that has a value of 0 in the case of a former-half cluster (sectors FC to 0D) and 1 in the case of a latter-half cluster (sectors 0E to 1F) is associated with AU5. An address bit ABLG for identifying recording areas of a disc having plural recording areas for land/groove recording or the like is set at 0. These bits of Au to AU18 and ABLG are associated with 15 bits s0 to s14 from the lower side of a 16-bit shift register for generating a pseudo-random number. Moreover, 1 is associated with the most significant bit s15. Thus, the error correction capability for high-density recording data can be improved.

Abstract: The present application relates to a copy-protected compact disc and a method for producing the optical disc and preventing unauthorized copying. The contents of at least one of the lead-in items in the optical disc are altered so that it is no longer uniform, thereby making a copied disc effectively corrupted and unplayable.

Abstract: Servo error signal circuitry apparatus and methods are described. The difference between two bottom envelope signals SEbtm and SFbtm is calculated by a subtracter (40) to generate a difference signal (SEbtm?SFbtm). The difference signal (SEbtm?SFbtm) is input as an alignment signal (AL) to an equalizer (42) and as a basic tracking error signal to the positive input terminal of a second subtracter (52). On the other hand, the difference between two top envelope signals SEtop and SFtop is calculated by a third subtracter (48) to generate a difference signal (SEtop?SFtop). The signal K(SEtop?SFtop) obtained by multiplying a coefficient K with the difference signal using a coefficient multiplier (50) is input to the negative input terminal of the second subtracter (52). The difference signal {(SEbtm?SFbtm)?K(SEtop?SFtop)} output from the second subtracter (52) is used as an offset corrected tracking error signal.

Abstract: An adaptive writing method of a high-density optical recording apparatus and a circuit thereof. The circuit includes a discriminator for discriminating a magnitude of a present mark of input NRZI data and magnitudes of leading and/or trailing spaces of the input NRZI data, a generator for controlling the waveform of a write pulse in accordance with the magnitude of the present mark of the input NRZI data and the magnitudes of the leading and/or trailing spaces of the input NRZI data to generate an adaptive write pulse, and a driver for driving a light source by converting the adaptive write pulse into a current signal in accordance with driving power levels for respective channels of the adaptive write pulse. The widths of the first and/or last pulses of the write pulse waveform are varied in accordance with the magnitude of the present mark of input NRZI data and the magnitude of the leading and/or trailing spaces, thereby minimizing jitter to enhance system reliability and performance.

Abstract: A copy-protected compact disc and a method for producing the optical disc and preventing unauthorized copying is provided. In one embodiment, the contents of at least one of the lead-in items in the optical disc are altered so that it is no longer uniform, thereby making a copied disc effectively corrupted and unplayable.

Abstract: An optical disk unit includes the following: a storage part temporarily storing data to be written to an optical disk; a processing part processing the data; an encoder part modulating and outputting the processed data; a writing control part controlling writing of the data to the optical disk; and a writing command part detecting an occurrence of a state of suspension of supply of the data to the storage part and providing an operation command to the writing control part in accordance with the detection result. In the case of suspending the writing of the data to the optical disk, the writing control part causes the processing and encoder parts to stop accessing the storage part by setting the processing and encoder parts in a wait state after the processing and encoder parts access the storage part, and causes the storing of the data in the storage part to be stopped.

Abstract: Disclosed is a disk-like recording medium, a disk recording apparatus and a disk recording method, and a disk playback apparatus and a disk playback method. Disk ID is recorded over a circle of a burst cutting area on an optical disk. The circle is divided into n blocks, each of the blocks is divided into m frames, and ID information is recorded in each of the frames with k channel bits.

Abstract: A compact high-density optical disc capable of securing recording/reproducing characteristics and high-density recording capacity. The high-density optical disc has a whole diameter of 80 mm or less to 28 mm, a whole thickness in a range of 0.3–0.7 mm, and a position where data starts being recorded in a range of 27–45 mm of the diameter. Thus, an existing disc drive can be used, the size of the high-density optical disc can be reduced, and high-density recording capacity can be secured.

Abstract: A method for verifying sectors on an optical disc is provided. The method includes writing user data to unverified sectors of the optical disc and verifying the sectors of the optical disc with the user data. The sectors of the optical disc are verified by reading the user data on the unverified sectors of the optical disc and comparing the user data read from the unverified sectors of the optical disc with user data stored on a system buffer. The sectors of the optical disc are verified to determine whether any one of the unverified sectors having user data is defective. Also, the verifying of the unverified sectors establishes verified sectors having user data. The sectors of the optical disc that have been verified are tracked with a bitmap that is continually updated as the sectors are verified.

Abstract: An information recording medium 1 at least comprises a substrate 13 having a microscopic pattern 20, which is constituted by a shape of continuous substance of approximately parallel grooves formed with a groove section G and a land section L alternately, a recording layer 12 formed on the microscopic pattern 20 and a light transmission layer 11 formed on the recording layer. The microscopic pattern 20 is formed so as to satisfy a relation of P<?/NA and a thickness of the light transmission layer 11 is within a range of 0.07 to 0.12 mm, wherein P is a pitch of the groove section G or the land section L, ? is a wavelength of reproducing light beam and NA is a numerical aperture of an objective lens. Further, there provided an information recording medium, which is improved in cross erase and recorded in high density, and a reproducing apparatus and a recording apparatus for the information recording medium.

Abstract: The mark-length recording system whereby information is recorded by changing the lengths of a recorded portion and an unrecorded or erased portion has a problem that, when new information is recorded in an already recorded region, the newly recorded information may deteriorate in reliability because the length and width of the newly recorded mark are different from those of the previously recorded mark and a part may exist that is not completely erased at the time of overwriting. The invention widens a setting freedom of the recording power and controls the length and width of the recorded mark by making the effective recording pulse length (the length from a rise of a first pulse to a fall of a last pulse) satisfy a relation: (effective recording pulse length)<(recording code length, i.e., the length of data to be recorded)?2T(twice the reference clock cycle).

Abstract: An optical pickup in which a substantially L-shaped retaining seat having an inclined side surface and an inclined end surface which are orthogonal to each other is formed on one side surface of a light passage hole formed in a housing, a groove is formed between the inclined side surface and the inclined end surface, while a positioning seat is formed on the other side surface of the light passage hole. An adhesive agent is injected between each of both end portions of a half mirror, which is disposed in an inclined state on the both seats, and each of the seats and into the groove. The width of an opening portion of the groove is set to be larger than the width of an depth portion of the groove.

Abstract: An optical head is provided, which suppresses the offset in the tracking error signal.

Abstract: A method for controlling an optical drive to record data onto a disc. The optical recorder has a pick up head for emitting laser onto the disc to record data onto the disc. The method includes adjusting a write power and a write strategy of the optical drive according to a linear velocity of the disc when passing by the pick up head.